Development of a medium tank (working designation 20/25TP) started in Poland in January 1937. The Armament and Technical Equipment Committee of the Polish Ministry of Military Affairs (KSUST, as abbreviated in Polish) suggested two versions of the vehicle. The second version featured 50 mm armor and an improved power unit. Existed only in blueprints.
Time for the successive autoreloading of each shell into the magazine.
Characteristics are specified for Siege mode.
Characteristics are specified for Rapid mode.
Characteristics are specified for vehicles with crews trained to 100%.